A combination of falling tax revenue and the state's decision to cut off funding for transit operations hit agencies hard. In addition to raising fares, agencies are looking at cutting service and laying off employees.

"If it wasn't for the worst economic downturn in a generation, we wouldn't be facing these sorts of increases," said Judson True, spokesman for Muni, the region's largest transit system.

The Bay Area is not alone. A survey released this month by the American Public Transportation Association found that the nation's economic mess has meant a loss in state, regional and local funding for 80 percent of the mass transit providers in the United States. Of those, almost 90 percent have raised fares, cut service or both.

"With state and local revenues declining due to the recession, public transit systems are facing severe financial challenges, and America's riders are paying the price," said association President William Millar.

In the Bay Area, Muni and AC Transit both will start charging $2 for a basic adult fare. That's a 25-cent increase for AC Transit and 50 cents higher for Muni.

Muni discount cash fares for seniors, youths and the disabled will jump to 75 cents, a 25-cent hike, and AC Transit's discount fares will go up to $1, a 15-cent increase.

Muni's monthly passes will cost more, too - from $45 to $55 for the adult pass, for example. AC Transit will raise the price of the regular adult monthly pass and for rides across the bay.

Even if BART management and its unions cannot agree on a new contract and workers strike, fares will increase by 6.1 percent. People riding Golden Gate buses and ferries will see a 5 percent across-the-board hike. Nondiscounted travel on a Golden Gate Transit bus from Novato to San Francisco, for example, will cost $5.85, a 30-cent increase.

A ride on BART from Walnut Creek to downtown San Francisco will cost $4.75, a 25-cent boost.

"A quarter here, 50 cents there may not seem like a lot, but day after day it starts to add up," said BART regular Ellie Green, who commutes from Berkeley to her grant-writing job in downtown San Francisco. "I know transportation agencies are hurting for money, but it's not like someone's putting more money in my pocket."

Other transit operators in the region have either approved fare increases or are considering them for implementation later this year or next year.